(Revised Abstract) DESCRIPTION (provided by applicant): The Mouse Genetics Facility was established in 1999 in response to the increasing need of Cancer Center investigators for analysis of gene function in the mouse. The facility was created and has been maintained solely supported by a large investment of Wistar funds. The primary goal of the Mouse Genetics Facility is to provide state of the art services to CCSG investigators for gene manipulation of mouse embryos thereby to create transgenic and gene knockout animals for cancer research projects. The facility is managed by Jaspal Khillan, Ph.D., who has over 15 years of experience with transgenic and knockout technology. Dr. Khillan devotes 100 percent effort to the management of the facility and manages a staff with extensive experience in mouse genetics, animal handling and molecular biology. The facility provides the full range of services that include generation of transgenic animals by DNA microinjection, preparation of gene targeted embryonic stem (ES) cells and chimeric animals for germline transmission, rederivation of transgenic lines, cryopreservation of embryos, and derivation of new ES cell lines from embryos. The availability of these technically demanding procedures within Wistar will enhance efficiency and reduce costs for each project and will facilitate new collaborations and interactions among Wistar scientists. Since its inception, the Mouse Genetics Facility has produced numerous transgenic and gene knockout mouse lines and has introduced specialized services to support the peer reviewed projects of the Wistar investigators. Key facility resources, which include training, specialized services, and the development of new mouse ES lines, will be useful to Cancer Center members as well as to the scientific community at large. In addition, the resources provided by this facility will be essential to the recruitment and success of the mouse geneticists who are part of our recruiting plan.